A. Field of the Invention
The present invention relates generally to rifle accuracy and, more particularly, to a method for improving the accuracy of rifles when shooting at a fixed distance, using varying velocity ammunition and when shooting in differing atmospheric conditions. In another aspect, the invention relates to a noise suppressor design for such a rifle.
B. Description of the Prior Art
There has always been a desire among marksmen for firearms to be as accurate and consistent as possible during firing. This desire is particularly characteristic of marksmen who engage in rifle target shooting competitions and so-called “bench rest” competitions. As a result, the prior art is replete with efforts to eliminate or at least minimize those factors that adversely affect rifle accuracy. Two factors which have been studied extensively in the past are: (1) the barrel vibration which occurs upon firing of the weapon; and (2) the recoil which the marksman absorbs upon firing the weapon. Attempts to eliminate or control barrel vibration and recoil have involved a variety of materials and techniques. For example, various types and kinds of bedding materials have been used as a shock absorber and dampener between the barrel and the action assemblies and stocks of a rifle. The kinds and positioning of mounting screws associated with the components of a rifle have been examined. Different stock and barrel configurations have been tried in the past.
Muzzle brakes are another type accessory which have been used in the past with rifles in an attempt to lessen the effects of recoil and thus improve accuracy. The known muzzle brakes function to exhaust propulsion gases as a means of reducing recoil and of dissipating propulsion gases in a direction or directions other than directly out the muzzle of the barrel.
Another approach to improving rifle accuracy has involved attaching a weight to the end of the muzzle as a means of dampening barrel vibrations set in motion by the discharge of the firearm. U.S. Pat. No. 4,726,280, for example, discloses a technique for improving rifle accuracy by mounting a muzzle member on the muzzle end of a gun barrel. RE. 35,381 describes the Browning BOSS™ ballistic optimizing system which uses a movable weight element secured to the muzzle end of a rifle barrel. The weight element can be moved axially along the muzzle region of the barrel to change the effective weight applied for vibration dampening purposes.
U.S. Pat. No. 5,423,145 describes a rifle barrel harmonic vibration tuning device in which a “contact means” is adjustably positionable along the underside of the rifle barrel. The contact means exerts a variable amount of pressure between the rifle stock and its barrel at any of a number of given position along the barrel in an attempt to control the barrel's harmonic vibrations. U.S. Pat. No. 3,340,641 is similar in its disclosure and shows another sliding contact member which is used in an attempt to control the harmonic vibrations of the rifle barrel.
Despite these various types of efforts, deficiencies continue to exist in achieving ultimate rifle accuracy. This is particularly true when firing of certain factory loaded cartridges with a barrel not designed specifically for use with that cartridge. For example, with a lower velocity ammunition, the bullet tends to leave the barrel later than a faster velocity ammunition. As a result, due to the force of recoil, the bullet exits the muzzle at a point at which the rifle barrel has risen upwards more than it would with the faster velocity ammunition. The bullet shot from the lower velocity ammunition will thus tend to strike the target higher than the higher velocity ammunition, at a certain fixed distance.
A need exists, therefore, for a method for improving rifle accuracy which could be “tuned” to compensate for ammunition of varying velocities, particularly when shooting at a fixed distance. This would be advantageous, for example, in bench rest competitions and in certain military situations.
While there are many “tuners” on the market today, the tuning achieved or converging of different velocities is only effective out to about 100 yards. It is not possible to completely converge different velocities at long ranges out to extreme ranges, e.g. 1000 yards, or more.
There is also a need in the arena of tactical firearms that are utilized by the military as well as law enforcement tactical and special operations personnel for military and law enforcement activities, to provide a noise suppressor for such weapons. Noise suppressors are also used in some civilian circumstances, as well, as will be explained.
As is well known who are familiar with and enjoy firearms, firearms create both a loud noise as well as a significant recoil when they are discharged. The noise and the recoil are generally proportional to the size of the bullets being discharged by the firearms. For example, a 22 caliber rifle produces less noise and recoil than does a high caliber hunting rifle such as a 30-06 caliber firearm. However, both large and small bore weapons generally produce an undesirably great noise and recoil when discharged. This is true with respect to almost all firearms including both rifles and pistols.
Noise suppressors, sometimes referred to as “silencers’ for firearms have been proposed and made for many decades. Noise suppressors are very popular on varmint rifles because one shot drives varmints underground for hours while noise suppressed rifles can be fired many times before the game becomes wary. The standard noise suppressor was originally proposed by Hiram Maxim and present commercially available silencers are manifest descendants. These suppressors are mounted on the muzzle end of a firearm so the round or shot and all propellant gases pass through the suppressor. Most present day suppressor designs are basically mufflers. Disclosures of these typical firearm noise suppressors are found in U.S. Pat. Nos. 916,885; 958,934; 958,935; 1,229,675; 2,449,571; and 3,713,362.
Rifle suppressors are typically threaded onto the outer end of a firearm barrel in order to reduce the noise of the firearm. These devices generally work to muffle or reduce the noise of the exhausting gases created by ignition of a cartridge without necessarily retarding the passage of the bullet through the gun barrel. In certain of the prior art designs, the noise suppressor is designed to effect rapid cooling of exhausting gases and the reduction of pressure therefrom before the gases emerge from the end of the noise suppressor device. Typically, the well-known noise suppressors have a large cross-sectional area providing a chamber through which a bullet passes that contains heat absorbing and/or exhaust gas-defusing materials.
Although most noise suppressors are large diameter cylindrical devices that are screwed onto the end of a firearm barrel, it is also known to provide a noise suppressor or silencer along the entire length of an enlarged-diameter rifle barrel.
While there have been a number of advances in art of firearms suppressors, there continues to be a need for improvement. For example, many of the present suppressor designs are large and bulky, making them awkward to handle, especially in tight quarters. Some have wearable components such as baffles and O-rings which wear over time. Many of the present designs fail to offer a self-cleaning feature.